9.0 OPERATING INSTRUCTIONS
IRN37–160K–OF & IRN50–200H–OF
http://air.irco.com
60
Start sequence
The compressor will initially start by pressing the local
start button or receiving a remote start command. The
Intellisys will energize the start output to start the
compressor. Both blowdown valves will de–energize to
start the unit unloaded. The compressor will ramp up
to its minimum speed. Once the minimum speed has
been achieved, the Intellisys will energize the
blowdown valves and the compressor will start to
control pressure by using its speed regulation. When
the system pressure approaches the target pressure,
the motor will start to slow. If the system pressure rises
to the immediate stop pressure set point, the Intellisys
will perform its stop sequence immediately. If the
Intellisys reaches its auto–stop pressure it will wait until
the drive is running at minimum speed and if pressure
is maintained above the auto–stop pressure, the
Intellisys will perform its stop sequence. Immediate
stop and auto–stop conditions will leave the
compressor in an auto–start state where it will
automatically start if the system pressure falls below
the target pressure. This process will continue until the
Intellisys receives a stop command or has an alarm
Stop sequence
The compressor has two stop sequences. If the
emergency stop button is pressed or if a shutdown
occurs as a result of an alarm, the start output will
de–energize and the compressor will stop immediately.
The emergency stop must be reset and the alarm must
be cleared before the compressor can be restarted.
If the pressure reaches the automatic stop or
immediate stop pressure or if the stop button (local or
remote) is pressed, the compressor will de–energize
the package discharge blowdown valve and
de–energize the condensate solenoid valves. The
compressor will then run for 10 seconds with the
package discharge valve open. The compressor will
stop after 10 seconds if the system pressure is greater
than the target pressure and if the second stage
discharge pressure is less than 55 psig. Immediate
stop and autostop conditions leave the compressor in
an auto–start state where it will automatically start if the
system pressure falls below the target pressure. The
compressor will not automatically restart if the local or
remote stop button is pressed.
Blower control
The blower speed varies to minimize energy
consumption while optimizing cooler performance. The
blower motor has its own variable speed drive and will
ramp up and down as the compressor starts and stops.
Stopping the machine in an emergency
If the machine has to be stopped in an emergency
DEPRESS THE
EMERGENCY STOP
BUTTON
LOCATED UNDERNEATH THE INSTRUMENT
PANEL.
This will over–ride the normal unload/stop button and
will immediately stop the machine.
Restarting after an emergency
If the unit has been switched off because of a machine
malfunction, identify and correct the fault before
attempting to restart.
If the unit has been switched off for reasons of safety,
ensure that the machine can be operated safely before
restarting.
Refer to the
PRIOR TO STARTING
and
START
SEQUENCE
instructions earlier in this section before
restarting the machine.
